FOSS gamedev and creative worlds

The mod could contain a box, which can be powered by mesecon (the mod would check to see if the mesecon mod is installed first), and user would be allowed to spawn up to 5 different items and set spawn conditions (Spawn when there arent any other mobs around, stop spawning when a player is nearby, etc.). What do you think about this idea?

You could power a technic filter connected to a chest using mesecons.
That's not exactly what you want but it also spawns items.

True...I was thinking about modding the Vombie Spawner mod myself but I don't know Lua.